Ligand and complex for catalytically bleaching a substrate

ABSTRACT

The invention relates to catalytically bleaching substrates, especially laundry fabrics, with atmospheric oxygen or air. A method of bleaching a substrate is provided that comprises applying to the substrate, in an aqueous medium, a specified ligand from a selected class which forms a complex with a transition metal, the complex catalysing bleaching of the substrate by atmospheric oxygen. Also provided is an aqueous bleaching composition substantially devoid of peroxygen bleach or a peroxy-based or -generating bleach system.

FIELD OF INVENTION

This invention relates to a class of ligand or complex thereof useful ascatalysts for catalytically bleaching substrates with atmosphericoxygen.

BACKGROUND OF INVENTION

The use of bleaching catalysts for stain removal has been developed overrecent years. The recent discovery that some catalysts are capable ofbleaching effectively in the absence of an added peroxyl source hasrecently become the focus of some interest, for example: WO9965905;WO0012607; WO0012808; and, WO0029537.

The search for new classes of compounds that are suitable as airbleaching catalyst is ongoing.

Various [3.3.1] bicyclo compounds and complexes thereof are discussed inthe literature, see for example: Comba P. et al., J. Chem. Soc. DaltonTrans, 1998, (23) 3997-4001; Börzel et al. Chem. Eur. J. 1999, 5, No. 6,1716 to 1721 and review by P. Comba in Coordination Chemistry Reviews2000, 200-202, 217 to 245, entitled “Coordination compounds in theEntactic State”. These compounds are discussed in terms of theirphysical properties.

WO0060045 discloses a bleaching system comprising: a) from about lppb,by weight of a transition metal catalyst comprising: i) a transitionmetal; ii) a ligand having formula (I):

wherein each R is independently hydrogen, hydroxyl, C1-C4 alkyl, andmixtures thereof; R1 is C1-C4 alkyl, C6-C10 aryl, and mixtures thereof;R2 is C1-C4 alkyl, C6-C10 aryl, and mixtures thereof; R3 and R4 are eachindependently hydrogen, C1-C8 alkyl, C1-C8 hydroxyalkyl, —(CH₂)_(x)CO₂R5wherein R5 is C1-C4 alkyl, x is from 0 to 4, and mixtures thereof; X iscarbonyl, —C(R6)2— wherein each R6 is independently hydrogen, hydroxyl,C1-C4 alkyl, and mixtures thereof; b) optionally a source of hydrogenperoxide; and c) the balance carriers and adjunct ingredients. However,the teaching of WO0060045 limits substituents at the nitrogens (3 and 7positions) of bicyclostructure to homoaromatic carbon groups, namelyalkyl and aryl.

SUMMARY OF INVENTION

We have found that the presence of a group bearing a heteroatom on oneor more of the nitrogens of the bicyclostructure provides an enhancedactivity. The compounds provided are surprisingly active as airbleaching catalysts. In addition, we also found that similar compoundsare surprisingly active and provide novel ligands and transition metalcomplexes thereof for use in air bleaching.

Accordingly, in a first aspect, the present invention provides ableaching composition comprising:

A bleaching composition comprising:

a) a monomer ligand or transition metal catalyst thereof of a ligandhaving the formula (I):

wherein each R is independently selected from: hydrogen, F, Cl, Br,hydroxyl, C1-C4-alkylO—, —NH—CO—H, —NH—CO-C1-C4-alkyl, —NH2,—NH-C1-C4-alkyl, and C1-C4-alkyl; R1 and R2 are independently selectedfrom:

C1-C4-alkyl,

C6-C10-aryl, and,

a group containing a heteroatom capable of coordinating to a transitionmetal, wherein at least one of R1 and R2 is the group containing theheteroatom;

R3 and R4 are independently selected from hydrogen, C1-C8 alkyl,C1-C8-alkyl-O-C1-C8-alkyl, C1-C8-alkyl-O-C6-C10-aryl, C6-C10-aryl,C1-C8-hydroxyalkyl, and —(CH2)_(n)C(O)OR5 wherein R5 is independentlyselected from: hydrogen, C1-C4-alkyl, n is from 0 to 4, and mixturesthereof; and,

X is selected from C═O, —[C(R6)₂]_(y)— wherein Y is from 0 to 3 each R6is independently selected from hydrogen, hydroxyl, C1-C4-alkoxy andC1-C4-alkyl; and,

b) the balance carriers and adjunct ingredients.

Preferred groups containing the heteroatom may be found in aheterocycloalkyl: selected from the group consisting of: pyrrolinyl;pyrrolidinyl; morpholinyl; piperidinyl; piperazinyl; hexamethyleneimine; 1,4-piperazinyl; tetrahydrothiophenyl; tetrahydrofuranyl;tetrahydropyranyl; and oxazolidinyl, wherein the heterocycloalkyl may beconnected to the ligand via any atom in the ring of the selectedheterocycloalkyl,

a -C1-C6-alkyl-heterocycloalkyl, wherein the heterocycloalkyl of the-C1-C6-heterocycloalkyl is selected from the group consisting of:piperidinyl; piperidine; 1,4-piperazine, tetrahydrothiophene;tetrahydrofuran; pyrrolidine; and tetrahydropyran, wherein theheterocycloalkyl may be connected to the -C1-C6-alkyl via any atom inthe ring of the selected heterocycloalkyl, a -C1-C6-alkyl-heteroaryl,wherein the heteroaryl of the -C1-C6-alkylheteroaryl is selected fromthe group consisting of: pyridinyl; pyrimidinyl; pyrazinyl; triazolyl;pyridazinyl; 1,3,5-triazinyl; quinolinyl; isoquinolinyl; quinoxalinyl;imidazolyl; pyrazolyl; benzimidazolyl; thiazolyl; oxazolidinyl;pyrrolyl; carbazolyl; indolyl; and isoindolyl, wherein the heteroarylmay be connected to the -C1-C6-alkyl via any atom in the ring of theselected heteroaryl and the selected heteroaryl is optionallysubstituted by -C1-C4-alkyl,

a -C0-C6-alkyl-phenol or thiophenol,

a -C2-C4-alkyl-thiol, thioether or alcohol,

a -C2-C4-alkyl-amine, and

a -C2-C4-alkyl-carboxylate.

In a second aspect, the present invention provides a bleachingcomposition comprising, in an aqueous medium, atmospheric oxygen and abicyclo ligand of the general Formula (I) which forms a complex with atransition metal, the complex catalysing bleaching of a substrate by theatmospheric oxygen, wherein the aqueous medium is substantially devoidof peroxygen bleach or a peroxy-based or -generating bleach system. Itis preferred that the medium has a pH value in the range from pH 6 to 11and most preferably from pH 8 to 10.

The present invention also provides novel compounds of the generalFormula (I) with the proviso that the following compounds are excluded:dimethyl2,4-di-(2-pyridyl)-3,7-bis-(pyridin-2-ylmethyl)-3,7-diaza-bicyclo[3.3.1]nonan-9-one-1,5-dicarboxylate;1,5-bis-(hydroxymethylene)-2,4-di-(2-pyridyl)-3,7-bis-(pyridin-2-ylmethyl)-3,7-diazabicyclo[3.3.1]nonan-9-ol;dimethyl2,4-di-(2-pyridyl)-3,7-bis-(pyridin-2-ylethyl)-3,7-diaza-bicyclo[3.3.1]nonan-9-one-1,5-dicarboxylate;dimethyl2,4-di-(2-pyridyl)-3-(5-carboxypentyl)-7-methyl-3,7-diaza-bicyclo[3.3.1]nonan-9-one-1,5-dicarboxylate;dimethyl2,4-di-(2-pyridyl)-3-(2-methoxyethyl)-7-methyl-3,7-diaza-bicyclo[3.3.1]nonan-9-one-1,5-dicarboxylate;diethyl-2,4-dipyridyl-7-picolyl-3,7-diaza-bicyclo-[3.3.1]-nonan-9-one-1,5-dicarboxylate;diethyl-2,4-dipyridyl-7-benzyl-3-hydroxyethyl-3,7-diaza-bicyclo-[3.3.1]-nonan-9-one-1,5-dicarboxylate;and,dimethyl-2,4-dipyridyl-7-benzyl-3-hydroxyethyl-3,7-diaza-bicyclo-[3.3.1]-nonan-9-one-1,5-dicarboxylate.

An advantage of the class of ligand and complex according to the presentinvention is that the complex can catalyse bleaching of a substrate byatmospheric oxygen, thus permitting its use in a medium such as anaqueous medium that is substantially devoid of peroxygen bleach or aperoxy-based or -generating bleach system. We have also found thatcomplexes of this class are surprisingly effective in catalysingbleaching of the substrate by atmospheric oxygen after treatment of thesubstrate. The composition of the present invention bleaches a substratewith at least 10%, preferably at least 50% and optimally at least 90% ofany bleaching of the substrate being effected by oxygen sourced from theair.

One skilled in the art will appreciate that not all peroxyl activatingcatalysts are capable of functioning as an oxygen activation catalyst.However, the converse is not true. There is no evidence to indicate thatany oxygen activation catalyst will not function as peroxyl activatingcatalyst. In this regard, all oxygen activation catalysts disclosedherein may be used as a peroxyl activating catalyst. Catalysts of thepresent invention may be incorporated into a composition together with aperoxyl species or source thereof. For a discussion of acceptable rangesof a peroxyl species or source thereof and other adjuvants that may bepresent the reader is directed to U.S. Pat. No. 6,022,490, the contentsof which are incorporated by reference.

The present invention extends to a method of bleaching a substratecomprising applying to the substrate, in an aqueous medium, thebleaching composition according to the present invention.

The present invention extends to a commercial package comprising thebleaching composition according to the present invention together withinstructions for its use.

The present invention further provides a dry textile having an organicsubstance as defined above applied or deposited thereon, wherebybleaching by atmospheric oxygen is catalysed on the textile.

Advantageously, by enabling a bleaching effect even after the textilehas been treated, the benefits of bleaching can be prolonged on thetextile. Furthermore, since a bleaching effect is conferred to thetextile after the treatment, the treatment itself, such as a laundrywash cycle, may for example be shortened. Moreover, since a bleachingeffect is achieved by atmospheric oxygen after treatment of the textile,hydrogen peroxide or peroxy-based bleach systems can be omitted from thetreatment substance.

The organic substance may be contacted to the textile fabric in anysuitable manner. For example, it may be applied in dry form, such as inpowder form, or in a liquor that is then dried, for example as anaqueous spray-on fabric treatment fluid or a wash liquor for laundrycleaning, or a non-aqueous dry cleaning fluid or spray-on aerosol fluid.Other suitable means of contacting the organic substance to the textilemay be used, as further explained below.

Any suitable textile that is susceptible to bleaching or one that onemight wish to subject to bleaching may be used. Preferably the textileis a laundry fabric or garment.

In a preferred embodiment, the method according to the present inventionis carried out on a laundry fabric using an aqueous treatment liquor. Inparticular, the treatment may be effected in a wash cycle for cleaninglaundry. More preferably, the treatment is carried out in an aqueousdetergent bleach wash liquid.

In a preferred embodiment, the treated textile is dried, by allowing itto dry under ambient temperature or at elevated temperatures. Theelevated temperatures are commonly provided by a heated agitatedenvironment, as for example found in a tumble dryer, which has beenfound to accelerate and enhance the air bleaching effect.

The bleaching method may be carried out by simply leaving the substratein contact with the organic substance for a sufficient period of time.Preferably, however, the organic substance is in an aqueous medium, andthe aqueous medium on or containing the substrate is agitated.

The organic substance can be contacted with the textile fabric in anyconventional manner. For example it may be applied in dry form, such asin powder form, or in a liquor that is then dried, for example in anaqueous spray-on fabric treatment fluid or a wash liquor for laundrycleaning, or a non-aqueous dry cleaning fluid or spray-on aerosol fluid.

In a preferred embodiment, the treated textile is dried, by allowing itto dry under ambient temperature or at elevated temperatures.

In a particularly preferred embodiment the method according to thepresent invention is carried out on a laundry fabric using aqueoustreatment liquor. In particular the treatment may be effected in, or asan adjunct to, an essentially conventional wash cycle for cleaninglaundry. More preferably, the treatment is carried out in an aqueousdetergent wash liquor. The organic substance can be delivered into thewash liquor from a powder, granule, pellet, tablet, block, bar or othersuch solid form. The solid form can comprise a carrier, which can beparticulate, sheet-like or comprise a three-dimensional object. Thecarrier can be dispersible or soluble in the wash liquor or may remainsubstantially intact. In other embodiments, the organic substance can bedelivered into the wash liquor from a paste, gel or liquid concentrate.

It is particularly advantageous that the organic substance used in themethod of the present invention makes use of atmospheric oxygen in itsbleaching activity. This avoids the requirement that peroxygen bleachesand/or other relatively large quantities of reactive substances need beused in the treatment process. Consequently, only a relatively smallquantity of bleach active substance need be employed and this allowsdosage routes to be exploited that could previously not be used. Thus,while it is preferable to include the organic substance in a compositionthat is normally used in a washing process, such as a pre-treatment,main-wash, conditioning composition or ironing aid, other means forensuring that the organic substance is present in the wash liquor may beenvisaged.

For example, it is envisaged that the organic substance can be presentedin the form of a body from which it is slowly released during the wholeor part of the laundry process. Such release can occur over the courseof a single wash or over the course of a plurality of washes. In thelatter case it is envisaged that the organic substance can be releasedfrom a carrier substrate used in association with the wash process, e.g.from a body placed in the dispenser drawer of a washing machine,elsewhere in the delivery system or in the drum of the washing machine.When used in the drum of the washing machine the carrier can be freelymoving or fixed relative to the drum. Such fixing can be achieved bymechanical means, for example by barbs that interact with the drum wall,or employ other forces, for example a magnetic force. The modificationof a washing machine to provide for means to hold and retain such acarrier is envisaged similar means being known from the analogous art oftoilet block manufacture. Freely moving carriers such as shuttles fordosage of surfactant materials and/or other detergent ingredients intothe wash can comprise means for the release of the organic substanceinto the wash.

In the alternative, the organic substance can be presented in the formof a wash additive that preferably is soluble. The additive can take anyof the physical forms used for wash additives, including powder,granule, pellet, sheet, tablet, block, bar or other such solid form ortake the form of a paste, gel or liquid. Dosage of the additive can beunitary or in a quantity determined by the user. While it is envisagedthat such additives can be used in the main washing cycle, the use ofthem in the conditioning or drying cycle is not hereby excluded.

The present invention is not limited to those circumstances in which awashing machine is employed, but can be applied where washing isperformed in some alternative vessel. In these circumstances it isenvisaged that the organic substance can be delivered by means of slowrelease from the bowl, bucket or other vessel which is being employed,or from any implement which is being employed, such as a brush, bat ordolly, or from any suitable applicator.

Suitable pre-treatment means for application of the organic substance tothe textile material prior to the main wash include sprays, pens,roller-ball devices, bars, soft solid applicator sticks and impregnatedcloths or cloths containing microcapsules. Such means are well known inthe analogous art of deodorant application and/or in spot treatment oftextiles. Similar means for application are employed in thoseembodiments where the organic substance is applied after the mainwashing and/or conditioning steps have been performed, e.g. prior to orafter ironing or drying of the cloth. For example, the organic substancemay be applied using tapes, sheets or sticking plasters coated orimpregnated with the substance, or containing microcapsules of thesubstance. The organic substance may for example be incorporated into adrier sheet so as to be activated or released during a tumble-driercycle, or the substance can be provided in an impregnated ormicrocapsule-containing sheet so as to be delivered to the textile whenironed.

Many transition metal complexes have high extinction coefficients in thevisible. In this regard, use over time may result in some colourdeposition on a substrate after repeated washing. The addition of alimited amount of a peroxyl source serves to reduce colour deposition inthose instances in which it occurs whilst still permitting airbleaching. Nevertheless, we have found that in certain instances thefree ligand may be used in the bleaching composition of the presentinvention. By using a free ligand, a bleaching formulation may preparedthat is consistent with consumer formulation colour expectation. In sucha formulation the metal ion may be provided by the composition or bytrace metals found in the stain.

DETAILED DESCRIPTION OF THE INVENTION

The ligand as described herein is capable of dynamic inversion. Theability of the ligand to chelate to a TM depends upon thestereochemistry of the substituents. It is preferred that subsituentsare endo-endo, but it is likely that stereochemical conversion takesplace by retro-Mannich conversion. Retro-Mannich may be prevented bychanging the groups present such that retro-Mannich reactions areunfavoured. Nevertheless, it is likely that endo-exo and exo-exo ligandsas described herein coordinate to transition metal ions in manyinstances and are capable of functioning as air bleaching catalysts.

Referring to ligands and complexes thereof and bleaching compositionsderived therefrom with respect to Formula (I), it is preferred that eachR is the same; and R3=R4, and more preferred that R3 and R4 are the sameand are —(CH2)_(n)C(O)O-C1-C4-alkyl. It is even more preferred that R3and R4 are selected from the group consisting of —CH2OH,—C(O)O-C1-C6-alkyl, and phenyl.

Referring to X, it is preferred that Y=1, and most preferred wherein Xis C═O.

It is preferred that at least one of R1 and R2 is a3—CO—C6-alkyl-pyridin-2-yl-CO-C6-alkyl. It is most preferred that atleast one of R1 and R2 is selected from the group consisting of:3-ethyl-pyridin-2-ylmethyl, pyridin-2-ylmethyl,3-methyl-pyridin-2-ylmethyl, and 6-amide-pyridin-2-ylmethyl, of whichpyridin-2-ylmethyl is preferred from this group. It is even morepreferred that both R1 and R2 are selected from this group.

The catalyst may be used as a preformed complex of the ligand and atransition metal. Alternatively, the catalyst may be formed from thefree ligand that complexes with a transition metal already present inthe water or that complexes with a transition metal present in thesubstrate. The composition may also be formulated as a composition ofthe free ligand or a transition metal-substitutable metal-ligandcomplex, and a source of transition metal, whereby the complex is formedin situ in the medium.

The ligand forms a complex with one or more transition metals, in thelatter case for example as a dinuclear complex. Suitable transitionmetals include for example: manganese in oxidation states II-V, ironII-V, copper I-III, cobalt I-III, titanium II-IV, tungsten IV-VI,vanadium II-V and molybdenum II-VI.

The ligand forms a complex of the general formula (A1):[M_(a)L_(k)X_(n)]Y_(m)  (A1)in which:

M represents a metal selected from Mn(II)-(III)-(IV)-(V),Cu(I)-(II)-(III), Fe(II)-(III)-(IV)-(V), Co(I)-(II)-(III),Ti(II)-(III)-(IV), V(II)-(III)-(IV)-(V), Mo(II)-(III)-(IV)-(V)-(VI) andW(IV)-(V)-(VI), preferably selected from Fe(II)-(III)-(IV)-(V);

L represents a ligand as herein defined, or its protonated ordeprotonated analogue;

X represents a coordinating species selected from any mono, bi or tricharged anions and any neutral molecules able to coordinate the metal ina mono, bi or tridentate manner, preferably selected from O²⁻, RBO₂ ²⁻,RCOO⁻, RCONR⁻, OH⁻, NO₃ ⁻, NO, S²⁻, RS⁻, PO₄ ³⁻, PO₃OR³⁻, H₂O, CO₃ ²⁻,HCO₃ ⁻, ROH, N(R)₃, ROO⁻, O₂ ²⁻, O₂ ⁻, RCN, Cl⁻, Br⁻, OCN⁻, SCN⁻, CN⁻,N₃ ⁻, F⁻, I⁻, RO⁻, ClO₄ ⁻, and CF₃SO₃ ⁻, and more preferably selectedfrom O₂ ⁻, RBO₂ ²⁻, RCOO⁻, OH⁻, NO₃ ⁻, S²⁻, RS⁻, PO₃ ⁴⁻, H₂O, CO₃ ²⁻,HCO₃ ⁻, ROH, N(R)₃, Cl⁻, Br⁻, OCN⁻, SCN⁻, RCN, N₃ ⁻, F⁻, I⁻, RO⁻, ClO₄⁻, and CF₃SO₃ ⁻;

Y represents any non-coordinated counter ion, preferably selected fromClO₄ ⁻, BR₄ ⁻, [MX₄]⁻, [MX₄]²⁻, PF₆ ⁻, RCOO⁻, NO₃ ⁻, RO⁻, N⁺(R)₄, ROO⁻,O₂ ²⁻, O₂ ⁻, Cl⁻, Br⁻, F⁻, I⁻, CF₃SO₃ ⁻, S₂O₆ ²⁻, OCN—, SCN—, H₂O, RBO₂₂ ²⁻, BF₄ and BPh₄ ⁻, and more preferably selected from ClO₄ ⁻, BR₄ ⁻,[FeCl₄]⁻, PF₆ ⁻, RCOO⁻, NO₃ ⁻, RO⁻, N⁺(R)₄, Cl⁻, Br⁻, F⁻, I⁻, CF₃SO₃ ⁻,S₂O₆ ²⁻, OCN⁻, SCN⁻, H₂O and BF₄ ⁻;

a represents an integer from 1 to 10, preferably from 1 to 4;

k represents an integer from 1 to 10;

n represents an integer from 1 to 10, preferably from 1 to 4;

m represents zero or an integer from 1 to 20, preferably from 1 to 8;and

each R independently represents a group selected from hydrogen,hydroxyl, —R′ and —OR′ , wherein R′=alkyl, alkenyl, cycloalkyl,heterocycloalkyl, aryl, heteroaryl or a carbonyl derivative group, R′being optionally substituted by one or more functional groups E, whereinE independently represents a functional group selected from —F, —Cl,—Br, —I, —OH, —OR′, —NH₂, —NHR′, —N(R′)₂, —N(R′)₃ ⁺, —C(O)R′, —OC(O)R′,—COOH, —COO⁻ (Na⁺, K⁺), —COOR′, —C(O)NH₂, —C(O)NHR′, —C(O)N(R′)₂,heteroaryl, —R′, —SR′, —SH, —P(R′)₂, —P(O)(R′)₂, —P(O)(OH)₂, P(O)(OR′)₂,—NO₂, —SO₃H, —SO₃ ⁻(Na⁺, K⁺), —S(O)₂R′, —NHC(O)R′, and —N(R′)C(O)R′,wherein R′ represents cycloalkyl, aryl, arylalkyl, or alkyl optionallysubstituted by —F, —Cl, —Br, —I, —NH₃ ⁺, —SO₃H, —SO₃ ⁻(Na⁺, K⁺), —COOH,—COO⁻(Na⁺, K⁺), —P(O)(OH)₂, or —P(O)(O⁻(Na⁺, K⁺))₂, and preferably eachR independently represents hydrogen, optionally substituted alkyl oroptionally substituted aryl, more preferably hydrogen or optionallysubstituted phenyl, naphthyl or C₁₋₄-alkyl.

The counter ions Y in formula (A1) balance the charge z on the complexformed by the ligand L, metal M and coordinating species X. Thus, if thecharge z is positive, Y may be an anion such as RCOO⁻, BPh₄ ⁻, ClO₄ ⁻,BF₄ ⁻, PF₆ ⁻, RSO₃ ⁻, RSO₄ ⁻, SO₄ ²⁻, NO₃ ⁻, F⁻, Cl⁻, Br⁻, or I⁻, with Rbeing hydrogen, optionally substituted alkyl or optionally substitutedaryl. If z is negative, Y may be a common cation such as an alkalimetal, alkaline earth metal or (alkyl)ammonium cation.

Suitable counter ions Y include those which give rise to the formationof storage-stable solids. Preferred counter ions for the preferred metalcomplexes are selected from R⁷COO⁻, ClO₄ ⁻, BF₄ ⁻, PF₆ ⁻, RSO₃ ⁻ (inparticular CF₃SO₃ ⁻), RSO₄ ⁻, SO₄ ²⁻, NO₃ ⁻, F⁻, Cl⁻, Br⁻, and I⁻,wherein R represents hydrogen or optionally substituted phenyl, naphthylor C₁-C₄ alkyl.

The novel compounds of Formula (I) as provided by the present inventionalso extend to their various transition metal complexes, the transitionmetal complexes are as discussed above with reference to (A1).

It will be appreciated that the complex (A1) can be formed by anyappropriate means, including in situ formation whereby precursors of thecomplex are transformed into the active complex of general formula (A1)under conditions of storage or use. Preferably, the complex is formed asa well-defined complex or in a solvent mixture comprising a salt of themetal M and the ligand L or ligand L-generating species. Alternatively,the catalyst may be formed in situ from suitable precursors for thecomplex, for example in a solution or dispersion containing theprecursor materials. In one such example, the active catalyst may beformed in situ in a mixture comprising a salt of the metal M and theligand L, or a ligand L-generating species, in a suitable solvent. Thus,for example, if M is iron, an iron salt such as FeSO₄ can be mixed insolution with the ligand L, or a ligand L-generating species, to formthe active complex. Thus, for example, the composition may formed from amixture of the ligand L and a metal salt MX_(n) in which preferablyn=1-5, more preferably 1-3. In another such example, the ligand L, or aligand L-generating species, can be mixed with metal M ions present inthe substrate or wash liquor to form the active catalyst in situ.Suitable ligand L-generating species include metal-free compounds ormetal coordination complexes that comprise the ligand L and can besubstituted by metal M ions to form the active complex according theformula (A1).

The catalysts according to the present invention may be used for laundrycleaning, hard surface cleaning (including cleaning of lavatories,kitchen work surfaces, floors, mechanical ware washing etc.). As isgenerally known in the art, bleaching compositions are also employed inwaste-water treatment, pulp bleaching during the manufacture of paper,leather manufacture, dye transfer inhibition, food processing, starchbleaching, sterilisation, whitening in oral hygiene preparations and/orcontact lens disinfection.

In typical washing compositions the level of the organic substance issuch that the in-use level is from 1 μM to 50 mM, with preferred in-uselevels for domestic laundry operations falling in the range 10 to 100μM. Higher levels may be desired and applied in industrial bleachingprocesses, such as textile and paper pulp bleaching. These levelsreflect the amount of catalyst that may be present in a wash dose of adetergent composition. The bleaching composition comprises at least 1ppb of the ligand or complex thereof.

In the context of the present invention, bleaching should be understoodas relating generally to the decolourisation of stains or of othermaterials attached to or associated with a substrate. However, it isenvisaged that the present invention can be applied where a requirementis the removal and/or neutralisation by an oxidative bleaching reactionof malodours or other undesirable components attached to or otherwiseassociated with a substrate. Furthermore, in the context of the presentinvention bleaching is to be understood as being restricted to anybleaching mechanism or process that does not require the presence oflight or activation by light.

Synthesis

In addition to the utility of the ligands and complexes of the presentinvention as catalysts another advantage is that the ligands aregenerally relatively easy to synthesise in comparison to other ligands.The following is one example of a strategic synthetic approach; it willbe evident to one skilled in the art of synthetic organic chemistry thatmany approaches may be taken to obtain ligands and complexes for use inthe present invention. The ease of synthesis of the ligand of Formula(I) is dependent upon the nature of substituents about the structure.The ligands of Formula (I) are most preferably symmetric. Synthesis ofthese types of molecules are found in articles by U. Holzgrabe et al. inArch. Pharm. (Weinheim, Ger.) 1992, 325, 657 and A. Samhammer et al.Arch. Pharm. (Weinheim, Ger.) 1984, 322, 557. Below is given a schematicexample illustrating the ease of synthesis. The synthesis is shown in atwo step synthesis, Scheme 1 and Scheme 2, but in some cases may beconducted as a “one-pot” synthesis depending upon the nature of thesubstituents. Nevertheless, where substituents R7=R8 are different fromR3=R4 a two step synthesis is preferred. The product of reaction asfound in Scheme 1 is referred to as dimethyl2,6-di-(2-pyridyl)-1-methyl-piperid-4-one-3,5-dicarboxylate (NPy2),which can easily tautomerize to the enol. The synthesis is exemplifiedin R. Haller, K. W. Merz, Pharm. Acta Helv., 1963, 442.

Another important intermediate that may be produced according to thegeneral teachings of Scheme 1 wherein methylamine (CH₃NH₂) is replacedby 2-aminomethyl-pyridine such that a product referred to as dimethyl2,6-di-(2-pyridyl)-1-(pyridin-2-ylmethyl)-piperid-4-one-3,5-dicarboxylate(NPy3) is produced, the structure of which is given below.

One skilled in the art will appreciate that whilst Ac [—CO(O)Me] is anelectron withdrawing group and electron withdrawing groups are generallypreferred to facilitate synthesis other groups will also allow thereaction to proceed. Examples of suitable electron withdrawing groupsare given above and will be evident to one skilled in the art. Thereaction is also driven by precipitation of the product from solution.

In instances, depending upon the nature of the substituents, for examplea phenolic group, it will be necessary to protect certain functionalgroups. The choice of protecting groups during synthesis to preventundesirable reactions will be evident to one skilled in the art. For adiscussion of protecting groups in organic synthesis the reader isdirected to T. W. Green and P. G. M. Wuts, Protective Groups In OrganicSynthesis 3nd Ed.; J. Wiley and Sons, 1999.

It will be evident that if a diamine is substituted for methylamine inthe reaction illustrated in Scheme 2 two structures may be linkedtogether via the 7 positions as found in the structure below.

In addition, if a diamine is substituted for methylamine in the reactionillustrated in Scheme 1 a NPy2 structure is formed that is linked at the3 positions. Obviously, this dimer would serve as a precursor to otherdimer and polymer type structures. The present invention is confined to“monomer” ligands and not the dimer and polymer units linked by acovalent bond as described above. The term “monomer” as used herein isused to exclude these products in which covalently linked polyligandtype structures are formed.

The Detergent Composition.

The air bleach catalyst and may be used in a detergent compositionspecifically suited for stain bleaching purposes, and this constitutes asecond aspect of the invention. To that extent, the compositioncomprises a surfactant and optionally other conventional detergentingredients. The invention in its second aspect provides an enzymaticdetergent composition which comprises from 0.1-50% by weight, based onthe total detergent composition, of one or more surfactants. Thissurfactant system may in turn comprise 0-95% by weight of one or moreanionic surfactants and 5 to 100% by weight of one or more nonionicsurfactants. The surfactant system may additionally contain amphotericor zwitterionic detergent compounds, but this in not normally desiredowing to their relatively high cost. The enzymatic detergent compositionaccording to the invention will generally be used as a dilution in waterof about 0.05 to 2%.

In general, the nonionic and anionic surfactants of the surfactantsystem may be chosen from the surfactants described “Surface ActiveAgents” Vol. 1, by Schwartz & Perry, Interscience 1949, Vol. 2 bySchwartz, Perry & Berch, Interscience 1958, in the current edition of“McCutcheon's Emulsifiers and Detergents” published by ManufacturingConfectioners Company or in “Tenside-Taschenbuch”, H. Stache, 2nd Edn.,Carl Hauser Verlag, 1981.

Suitable nonionic detergent compounds which may be used include, inparticular, the reaction products of compounds having a hydrophobicgroup and a reactive hydrogen atom, for example, aliphatic alcohols,acids, amides or alkyl phenols with alkylene oxides, especially ethyleneoxide either alone or with propylene oxide. Specific nonionic detergentcompounds are C₆-C₂₂ alkyl phenol-ethylene oxide condensates, generally5 to 25 EO, i.e. 5 to 25 units of ethylene oxide per molecule, and thecondensation products of aliphatic C₈-C₁₈ primary or secondary linear orbranched alcohols with ethylene oxide, generally 5 to 40 EO.

Suitable anionic detergent compounds which may be used are usuallywater-soluble alkali metal salts of organic sulphates and sulphonateshaving alkyl radicals containing from about 8 to about 22 carbon atoms,the term alkyl being used to include the alkyl portion of higher acylradicals. Examples of suitable synthetic anionic detergent compounds aresodium and potassium alkyl sulphates, especially those obtained bysulphating higher C₈-C₁₈ alcohols, produced for example from tallow orcoconut oil, sodium and potassium alkyl C₉-C₂₀ benzene sulphonates,particularly sodium linear secondary alkyl C₁₀-C₁₅ benzene sulphonates;and sodium alkyl glyceryl ether sulphates, especially those ethers ofthe higher alcohols derived from tallow or coconut oil and syntheticalcohols derived from petroleum. The preferred anionic detergentcompounds are sodium C₁₁-C₁₅ alkyl benzene sulphonates and sodiumC₁₂-C₁₅ alkyl sulphates. Also applicable are surfactants such as thosedescribed in EP-A-328 177 (Unilever), which show resistance tosalting-out, the alkyl polyglycoside surfactants described in EP-A-070074, and alkyl monoglycosides.

Preferred surfactant systems are mixtures of anionic with nonionicdetergent active materials, in particular the groups and examples ofanionic and nonionic surfactants pointed out in EP-A-346 995 (Unilever).Especially preferred is surfactant system that is a mixture of an alkalimetal salt of a C₁₆-C₁₈ primary alcohol sulphate together with a C₁₂-C₁₅primary alcohol 3-7 EO ethoxylate.

The nonionic detergent is preferably present in amounts greater than10%, e.g. 25-90% by weight of the surfactant system. Anionic surfactantscan be present for example in amounts in the range from about 5% toabout 40% by weight of the surfactant system.

The detergent composition may take any suitable physical form, such as apowder, granular composition, tablets, a paste or an anhydrous gel.

Enzymes

The detergent compositions of the present invention may additionallycomprise one or more enzymes, which provide cleaning performance, fabriccare and/or sanitation benefits.

Said enzymes include oxidoreductases, transferases, hydrolases, lyases,isomerases and ligases. Suitable members of these enzyme classes aredescribed in Enzyme nomenclature 1992: recommendations of theNomenclature Committee of the International Union of Biochemistry andMolecular Biology on the nomenclature and classification of enzymes,1992, TSEN 0-12-227165-3, Academic Press.

Examples of the hydrolases are carboxylic ester hydrolase, thiolesterhydrolase, phosphoric monoester hydrolase, and phosphoric diesterhydrolase which act on the ester bond; glycosidase which acts onO-glycosyl compounds; glycosylase hydrolysing N-glycosyl compounds;thioether hydrolase which acts on the ether bond; and exopeptidases andendopeptidases which act on the peptide bond. Preferable among them arecarboxylic ester hydrolase, glycosidase and exo- and endopeptidases.Specific examples of suitable hydrolases include (1) exopeptidases suchas aminopeptidase and carboxypeptidase A and B and endopeptidases suchas pepsin, pepsin B, chymosin, trypsin, chymotrypsin, elastase,enteropeptidase, cathepsin B, papain, chymopapain, ficain, thrombin,plasmin, renin, subtilisin, aspergillopepsin, collagenase, clostripain,kallikrein, gastricsin, cathepsin D, bromelain, chymotrypsin C,urokinase, cucumisin, oryzin, proteinase K, thermomycolin, thermitase,lactocepin, thermolysin, bacillolysin. Preferred among them issubtilisin; (2) glycosidases such as α-amylase, β-amylase, glucoamylase,isoamylase, cellulase, endo-1,3(4)-β-glucanase (β-glucanase), xylanase,dextranase, polygalacturonase (pectinase), lysozyme, invertase,hyaluronidase, pullulanase, neopullulanase, chitinase, arabinosidase,exocellobiohydrolase, hexosaminidase, mycodextranase,endo-1,4-β-mannanase (hemicellulase), xyloglucanase,endo-β-galactosidase (keratanase), mannanase and other saccharide gumdegrading enzymes as described in WO-A-99/09127. Preferred among themare α-amylase and cellulase; (3) carboxylic ester hydrolase includingcarboxylesterase, lipase, phospholipase, pectinesterase, cholesterolesterase, chlorophyllase, tannase and wax-ester hydrolase. Preferredamong them is lipase.

Examples of transferases and ligases are glutathione S-transferase andacid-thiol ligase as described in WO-A-98/59028 and xyloglycanendotransglycosylase as described in WO-A-98/38288.

Examples of lyases are hyaluronate lyase, pectate lyase, chondroitinase,pectin lyase, alginase II. Especially preferred is pectolyase, which isa mixture of pectinase and pectin lyase.

Examples of the oxidoreductases are oxidases such as glucose oxidase,methanol oxidase, bilirubin oxidase, catechol oxidase, laccase,peroxidases such as ligninase and those described in WO-A-97/31090,monooxygenase, dioxygenase such as lipoxygenase and other oxygenases asdescribed in WO-A-99/02632, WO-A-99/02638, WO-A-99/02639 and thecytochrome based enzymatic bleaching systems described in WO-A-99/02641.

The activity of oxidoreductases, in particular the phenol oxidisingenzymes in a process for bleaching stains on fabrics and/or dyes insolution and/or antimicrobial treatment can be enhanced by addingcertain organic compounds, called enhancers. Examples of enhancers are2,2′-azo-bis-(3-ethylbenzo-thiazoline-6-sulphonate (ABTS) andPhenothiazine-10-propionate (PTP). More enhancers are described inWO-A-94/12619, WO-A-94/12620, WO-A-94/12621, WO-A-97/11217,WO-A-99/23887. Enhancers are generally added at a level of 0.01% to 5%by weight of detergent composition.

Builders, polymers and other enzymes as optional ingredients may also bepresent as found in WO0060045.

Suitable detergency builders as optional ingredients may also be presentas found in WO0034427.

The invention will now be further illustrated by way of the followingnon-limiting examples:

EXAMPLES

[MeN4Py)FeCl]Cl

The ligand N,N-bis(pyridin-2-yl-methyl)-1,1-bis(pyridin-2-yl)-1-aminoethane (MeN4py) was preparedas described in EP 0 909 809 A2.

The ligand MeN4Py (33.7 g; 88.5 mmoles) was dissolved in 500 ml drymethanol. Small portions of FeCl₂.4H₂O (0.95 eq; 16.7 g; 84.0 mmoles)were added, yielding a clear red solution. After addition, the solutionwas stirred for 30 minutes at room temperature, after which the methanolwas removed (rotary-evaporator). The dry solid was ground and 150 ml ofethylacetate was added and the mixture was stirred until a fine redpowder was obtained. This powder was washed twice with ethyl acetate,dried in the air and further dried under reduced pressure vacuum at 40°C. El. Anal. Calc. for [Fe(MeN4py)Cl]Cl.2H₂O: C 53.03; H 5.16; N 12.89;Cl 13.07; Fe 10.01%. Found C 52.29/52.03; H 5.05/5.03; N 12.55/12.61;Cl: 12.73/12.69; Fe: 10.06/10.01%.

Dimethyl 2,6-di-(2-pyridyl)-1-methyl-piperid-4-one-3,5-dicarboxylate(NPy2) (MW: 383.4 g/mol)

Picolylaldehyde (83.1 mmol; 8 ml) was added drop wise to an ice-bathcooled solution of acetonedicarboxylic acid dimethyl ester (41.55 mmol,6 ml) in methanol (30 ml), subsequent addition of aqueous (40%)methylamine (41.55 ml, 4.8 ml) yielded an orange red solution. Thesolution was stirred for 5 min at 0° C. and then cooled to 18° C. Afterapproximately two days storage at 18° C. large crystals formed in thereaction mixture. The crystals were removed by filtration and washedwith cold ethanol and recrystallised from ethanol. Further concentrationof the filtrate yielded a further 10% of product. The total yield of thetitle compound was 12.43 g (78%).

¹H-NMR (CD₂Cl₂) (predominantly enol): 1.70 (s, 3H, —NMe); 3.60; 3.67(2s, 6H, -OMe); 4.19 (d, J=10 Hz, 1H, pipH4); 4.46 (d, J=10 Hz, 1H,pipH5); 4.81 (s, 1H, pipH2); 7.10-8.60 (m, 10H, pyHs)

Dimethyl2,6-di-(2-pyridine)-1-(pyridin-2-ylmethyl)-piperid-4-one-3,5-dicarboxylate(NPy3) (MW: 460.5 g/mol)

The process for the synthesis of NPy3 is substantially the same as foundabove for NPy2 except that the following precursors are used:acetonedicarboxylic acid dimethyl ester (0.05 mol; 7.2 ml);2-pyridinaldehyde (0.1 mol; 9.56 ml); and, picolylamine (0.05 ml; 5.1 mlto yield 19.31 g (84%).

¹H-NMR: (DCCl₃) (predominantly enol): 3.55; 3.81 (s, 6H, -OMe); 3.83 (s,2H, CH₂-py); 4.29 (d, J=12 Hz, 1H, pipH4); 4.81 (d, J=12 Hz, 1H, pipH5);4.89 (s, 1H, pipH2); 7.05-7.78 (m, 9H, pyHs); 8.42-8.48 (m, 2H, pyH6,pyH6); 8.62 (d, J=8 Hz), 1H, pyH6)

Dimethyl2,4-di-(2-pyridyl)-3,7-dimethyl-3,7-diaza-bicyclo[3.3.1]nonan-9one-1,5-dicarboxylate(N2Py2) (MW:438.5 g/mol)

To a suspension of NPy2 (26.1 mmol; 10 g) in 80 ml ethanol was added anaqueous (37%) formaldehyde solution (62.66 mmol, 5.64 ml) followed by anaqueous 40% solution of methylamine (31.33 ml; 3.6 ml). The reactionmixture was then heated at reflux for 5 min after which the reactionmixture was cooled to ambient temperature. Afar scratching the inside ofthe vessel holding the reaction mixture white crystals were formed.After filtration of the crystalline product, the product was washed withethanol and the crystalline product dried under produced pressure toyield 8.61 g (75.3%) of the title compound.

¹H-NMR (CD₂Cl₂): 2.00 (s, 3H, N7-Me); 2.22 (s, 3H, N3-Me) 2.45 (d, J=12Hz, 2H, bisH6ax, bisH8ax); 2.93 (d, J=12 Hz, 2H, bisH6eq, bisH8eq); 3.75(s, 6H, -OMe); 4.67 (s, 2H, bisH2, bisH4); 7.23 (m, 2H, pyH5); 7.80 (t,J=8 Hz, 2H, pyH4); 8.07 (d, J=8 Hz, 2H, pyH3); 8.49 (d, J=5 Hz, 2H,pyH6).

Dimethyl2,4-di-(2-pyridyl)-3-methyl-7-(pyridin-2-ylmethyl)-3,7-diaza-bicyclo[3.3.1]nonan-9-one-1,5-dicarboxylate(N2Py3o) (MW: 515.22 g/mol)

2-Aminomethyl-pyridine (4.3 g, 39.7 mmol) and formaldehyde (37% inwater) (6.5 mL, 79.4 mmol) were added to a suspension of NPy2 (12.71 g,33.1 mmol) in 200 mL ethanol. The suspension was stirred under refluxfor 30 minutes resulting in a clear brown solution. The solvent wasremoved under reduced pressure and the remaining solid was crystallisedfrom ethanol to yield the title compound as a white solid (4.2 g, 25%).

¹H-NMR (300 MHz, CDCl₃): 1.94 (s, 3H, N-Me), 2.68 (d, 2H, J=12 Hz,bisH6ax, bisH8ax-); 3.14 (d, 2H, J=12 Hz, bisH6eq, bisH8eq): 3.57 (s,2H, CH₂-Py), 3.76 (s, 6H, OMe), 4.66 (s, 2H, bisH2, bisH4), 7.09 (t, 2H,J=1.5 Hz, Py-H), 7.21 (t, 1H, J=6.0 Hz, Py-H), 7.33 (d, 1H, J=7.6 Hz,Py-H), 7.50 (t, 2H, J=1.7 Hz, Py-H), 7.66 (t, 1H, J=7.5 Hz, Py-H), 7.92(d, 2H, J=7.8 Hz, Py-H), 8.45 (d, 2H, J=4.0 Hz, Py-H), 8.62 (d, 1H,J=4.8 Hz, Py-H).

Dimethyl2,4-di-(2-pyridyl)-3-(pyrid-2-ylmethyl)-7-methyl-3,7-diaza-bicyclo[3.3.1]nonan-9-one-1,5-dicarboxylate(N2Py3u) (MW: 515.22 g/mol)

To a suspension of NPy3 (21.79 g, 47.3 mmol) in 250 mL ethanol was addedaqueous (40%) methylamine (4.8 mL, 56.7 mmol) and aqueous (37%)formaldehyde (9.2 ml, 113.4 mmol). The suspension was stirred underreflux for 3 h which resulted in a deep brown solution being formed. Thesolvent was removed under reduced pressure and the resulting green/brownsolid was recrystallized from ethanol to yield 6.58 g (27%) of the titlecompound as a white solid.

¹H-NMR (300 MHz, CDCl₃): 2.20 (s, 3H, N-Me), 2.56 (d, 2H, J=12 Hz,bisH6ax, bisH8ax), 2.98 (d, 2H, J_(HH)=12 Hz, bisH6eq, bisH8eq), 3.72(s, 8H, OMe, CH₂-Py), 5.42 (s, 2H, bisH2, bisH4), 6.76 (d, 1H, J=7.7 Hz,Py-H), 6.97 (t, 1H, J=5.7 Hz, Py-H), 7.13 (t, 2H, J=6.0 Hz, Py-H), 7.38(t, 2H, J=7.6 Hz, Py-H), 7.68 (t, 2H, J=7.6 Hz, Py-H), 8.06 (d, 1H,J=7.6 Hz, Py-H), 8.43 (d, 1H, J=4.6 Hz, Py-H), 8.47 (d, 2H, J=4.4 Hz,Py-H). Anal. Calcd for C₂₈H₂₉N₅O₅: C 65.23, H 5.67, N 13.58; found: C64.86, H 5.60, N 13.41.

Dimethyl2,4-di-(2-pyridyl)-3,7-bis-(pyridin-2-ylmethyl)-3,7-diaza-bicyclo[3.3.1]nonan-9-one-1,5-dicarboxylate(N2Py4) (MW: 594.7 g/mol)

To a heated solution of NPy3 (32.61 mmol; 15 g) in 25 ml THF an aqueous(40%) formaldehyde (78.3 mmol; 7.0 ml) solution was added drop wise,after which 2-aminomethyl-pyridine (39.1 mmol; 4 ml) was added drop wiseresulting in a dark solution. The mixture was further heated for 1 h at85° C. After the reaction mixture was cooled a greenish precipitate wasformed. The precipitate was then washed with cold ethanol andcrystallised from ethanol to yield the title compound, 4.75 g (25%). Insome instances no precipitate is formed and in this case it is advisableto remove the THF under reduced pressure to yield a black oil and add 5ml EtOH. After addition of the EtOH the title compound crystallises outafter 3 to 4 hrs.

¹H-NMR (CDCl₃): 2.87 (d, J=12 Hz, 2H, bisH6ax, bisH8ax); 3.46 (d, J=12Hz, 2H, bisH6eq, bisH8eq), 3.66-3.71 (m, 10H, -OMe, —CH₂-py); 5.35 (s,2H, bisH2, bisH4); 6.73-8.63 (m s, 20H, pyHs).

Table 1 exemplifies the structures of ligands of the present inventionthat were used in bleaching experiments.

Ligand R3 = R4 = —C(O)OMe N2Py4 R1 = R2 = pyridin-2-ylmethyl R3 = R4 =—C(O)OMe N2Py2 R1 = R2 = —CH3 R3 = R4 = —C(O)OMe N2Py3u R1 = Me R2 =pyridin-2-ylmethyl R3 = R4 = —C(O)OMe N2Py3o R1 = pyridin-2-ylmethyl R2= Me

General Synthesis of Complex From Ligand

A solution of 2 mmol metal salt (FeSO₄, FeCl₂, CuCl₂, Fe(ClO₄)₂ etc) in1 mL methanol was added to a solution of 2 mmol ligand in 1 mLacetonitrile. The clear dark (generally brown for Fe complex and bluefor Cu complex) solution was put in a diethylether diffusion bath. Afterseveral hours, coloured crystals precipitated from the solution.

[FeSO₄ (N2Py3o)]

(Dimethyl 2,4-di-(2pyridyl)-3-methyl-7-(pyridin-2-ylmethyl)-3,7-diaza-bicyclo[3.3.1]nonan-9-one-1,5-dicarboxylate)sulfatoiron(II)[C₂₈H₂₉FeN₅O₉S M=667,13 g/mol]

Anal. Calcd for C₂₈H₂₉FeNsO₉S: C 47.80, H 4.73, N 9.96; found +2H₂O: C47.16, H 4.91, N 9.84. FAB⁺MS(nitrobenzylalcohol): 686.1 (MH⁺+H₂O)

[FeSO₄(N2Py3u)]

((Dimethyl-2,4-di-(2-pyridyl)-3-(pyridin-2-ylmethyl)-7-methyl-3,7-diaza-bicyclo[3.3.1]nonan-9-one-1,5-dicarboxylate)sulfatoiron(II)(M=667,13 g/mol) Anal. Calcd for C₂₈H₂₉FeN₅O₉S: C 46.61, H 4.89, N 9.71;found +3H₂O: C 47.27, H 4.81, N 9.88. FAB⁺MS(nitrobenzylalcohol) 686.1(MH⁺+H₂O)

[FeCl(N2Py3o)]Cl

Chloro(dimethyl2,4-di-(2-pyridyl)-3-methyl-7-(pyridin-2-ylmethyl)-3,7-diaza-bicyclo[3.3.1]nonan-9-one-1,5-dicarboxylate)iron(II)-chloridehydrate Anal. Calcd for C₂₈H₂₉Cl₂FeN₅O₅:C 49.58, H 4.90, N 10.45; found+2H₂O: C 49.45, H 4.79, N 10.00. FAB⁺MS(nitrobenzylalcohol): 624.1 [FeCl(N2Py3o).H₂O]

[Fe (N2Py4)]Cl₂

(Dimethyl-2,4-di-(2-pyridyl)-3,7-bis-(pyridin-2-ylmethyl)-3,7-diaza-bicyclo[3.3.1]nonan-9-one-1,5-dicarboxylate)iron(II)-dichloride hydrate [C₃₃H₃₈Cl₂FeN₆O₆ M=741.44 g/mol], Anal. Calcd forC₃₃H₃₈Cl₂FeN₆O₆: C 53.75, H 4.65, N 11.40; found: C 53.20, H 4.74, N11.22. FAB⁺MS(Nitrobenzylalcohol): 683.1 [Fe (N2Py4) H₂O]

[Fe (NCCH₃)₂(triflate)₂]

The following reaction was performed under anhydrous conditions underargon using standard Schlenck/cannular techniques.

To a cooled stirred mixture of iron powder (5.6 g, 0.1 mol) inacetonitrile (60 ml) trifluoromethanesulfonic acid (0.2 mol, 17.7 ml)was added. After addition, the reaction mixture was heated for 45 min at90° C. The reaction mixture was cooled, after which remaining solidmaterial was filtered off. To the remaining solution 40 ml of diethylether was slowly added resulting in a white precipitate. The whiteprecipitate was filtered off under argon, and washed with 20 ml ofether. The hygroscopic material was stored under. Yield 31.7% (13.8 g).

[Fe(N2Py2)(triflate)₂] (MW: 792.46 g/mol)

In a water-free system, 0.23 mmol (100 mg) of [Fe (CH₃CN)₂(triflate)₂]and ligand (0.23 mmol; 100 mg) in dry acetonitrile is added. Via slowdiffusion of ether into this solution, the crystals with the ironcomplex are formed. The yield for this procedure is typically 50%. Anal.Calcd for FeC₂₅H₂₉N₄O₁₁S₂F₆ calc 38.91, H 3.51, N 8.40; found: C 38.86,H 3.41, N 8.32.

Bleaching Experiments

Bleaching results obtained on tomato stains for the different complexes(10 μM) or preformed ligand/iron species (by premixing 2 mM ligand/1 mMiron perchlorate in ethanol/water (1/1). The tomato stains were washedwith the LAS/buffer system (0.6 g/L NaLAS in 10 mM carbonate buffer) for30 min at 30° C. in a bottle containing 25 ml of the wash solution.After the wash, cloths were washed with water and dried in a tumbledrier till dryness.

The reflectance measurements were obtained using a Minolta™ 3700dspectrophotometer at 460 nm. The difference in reflectance before andafter the wash is defined as a ΔR460 value. The bleaching resultsobtained immediately after drying (t=0) are shown. All values expressedin ΔΔR 460 values (blank, LAS only substracted); typical errors are inthe order of 2 points. A higher value means a better bleachingperformance.

Table 2: Bleaching Results (ΔΔR 460) on Tomato Oil of the PreformedComplexes and Ligand/iron Salt Mixtures (Active)

TABLE 2 Active t = 0 N2Py4 + Fe(II) 10 [Fe(N2py3o)Cl]Cl 24[Fe(N2py3u)SO4] 22 N2py3u + Fe(II) 11 N2py3o + Fe(II) 20 [Fe(N2py2)Cl₂]7 N2py2 + Fe(II) 1

The results in Table 2 show the following:

A good bleaching activity is obtained on tomato oil stains withespecially the iron complexes containing N2Py3 ligands (u and o) and toa lesser extent the N2py4 ligand/iron mixture in air bleaching. In allcases the bleaching results are significantly better than theN2py2-containing systems (either Fe complex or ligand/iron saltmixture). It is noteworthy that the ligand in combination with iron saltis effective in air bleaching.

1. A monomer ligand or transition metal catalyst thereof of a ligandhaving the formula (I):

wherein each R is independently selected from: hydrogen, F, Cl, Br,hydroxyl, C1-C4-alkylO-, —NH—CO—H, —NH—CO-C1-C4-alkyl, —NH2,—NH-C1-C4-alkyl, and C1-C4-alkyl; R1 and R2 are independently selectedfrom: C1-C4-alkyl, C6-C10-aryl, and, a group containing a heteroatomcapable of coordinating to a transition metal, wherein at least one ofR1 and R2 is the group containing the heteroatom; R3 and R4 areindependently selected from hydrogen, C1-C8 alkyl,C1-C8-alkyl-O-C1-C8-alkyl, C1-C8-alkyl-O-C6-C10-aryl, C6-C10-aryl,C1-C8-hydroxyalkyl, and —(CH2)_(n)C(O)OR5 wherein R5 is independentlyselected from: hydrogen, C1-C6-alkyl, n is from 0 to 4, and mixturesthereof; and, X is selected from C═O, —[C(R6)₂]_(y)— wherein Y is from 0to 3 and each R6 is independently selected from hydrogen, hydroxyl,C1-C4-alkoxy and C1-C4-alkyl; and with the proviso that the followingcompounds are excluded: dimethyl2,4-di-(2-pyridyl)-3,7-bis-(pyridin-2-ylmethyl)-3,7-diaza-bicyclo[3.3.1]nonan-9-one-1,5-dicarboxylate;1,5-bis-(hydroxymethylene)-2,4-di-(2-pyridyl)-3,7-bis-(pyridin-2-ylmethyl)-3,7-diazabicyclo[3.3.1]nonan-9-ol;dimethyl2,4-di-(2-pyridyl)-3,7-bis-(pyridin-2-ylethyl)-3,7-diaza-bicyclo[3.3.1]nonan-9-one-1,5-dicarboxylate;dimethyl2,4-di-(2-pyridyl)-3-(5-carboxypentyl)-7-methyl-3,7-diaza-bicyclo[3.3.1]nonan-9-one-1,5-dicarboxylate;dimethyl2,4-di-(2-pyridyl)-3-(2-methoxyethyl)-7-methyl-3,7-diaza-bicyclo[3.3.1]nonan-9-one-1,5-dicarboxylate;diethyl-2,4-dipyridyl-7-picolyl-3,7-diaza-bicyclo-[3.3.1]-nonan-9-one-1,5-dicarboxylate;diethyl-2,4-dipyridyl-7-benzyl-3-hydroxyethyl-3,7-diaza-bicyclo-[3.3.1]-nonan-9-one-1,5-dicarboxylate;and,dimethyl-2,4-dipyridyl-7-benzyl-3-hydroxyethyl-3,7-diaza-bicyclo-[3.3.1]-nonan-9-one-1,5-dicarboxylate.2. A ligand or catalyst according to claim 1, wherein R1 and R2 are bothselected from a group containing a heteroatom capable of coordinating toa transition metal.
 3. A ligand or catalyst according to claim 1,wherein the group containing the heteroatom is: a heterocycloalkyl:selected from the group consisting of: pyrrolinyl; pyrrolidinyl;morpholinyl; piperidinyl; piperazinyl; hexamethylene imine;1,4-piperazinyl; tetrahydrothiophenyl; tetrahydrofuranyl;tetrahydropyranyl; and oxazolidinyl, wherein the heterocycloalkyl may beconnected to the ligand via any atom in the ring of the selectedheterocycloalkyl, a -C1-C6-alkyl-heterocycloalkyl, wherein theheterocycloalkyl of the -C1-C6-heterocycloalkyl is selected from thegroup consisting of: piperidinyl; piperidine; 1,4-piperazine,tetrahydrothiophene; tetrahydrofuran; pyrrolidine; and tetrahydropyran,wherein the heterocycloalkyl may be connected to the -C1-C6-alkyl viaany atom in the ring of the selected heterocycloalkyl, a-C1-C6-alkyl-heteroaryl, wherein the heteroaryl of the-C1-C6-alkylheteroaryl is selected from the group consisting of:pyridinyl; pyrimidinyl; pyrazinyl; triazolyl; pyridazinyl;1,3,5-triazinyl; quinolinyl; isoquinolinyl; quinoxalinyl; imidazolyl;pyrazolyl; benzimidazolyl; thiazolyl; oxazolidinyl; pyrrolyl;carbazolyl; indolyl; and isoindolyl, wherein the heteroaryl may beconnected to the -C1-C6-alkyl via any atom in the ring of the selectedheteroaryl and the selected heteroaryl is optionally substituted by-C1-C4-alkyl, a -C0-C6-alkyl-phenol or thiophenol, a -C2-C4-alkyl-thiol,thioether or alcohol, a -C2-C4-alkyl-amine, and a-C2-C4-alkyl-carboxylate.
 4. A ligand or catalyst according to claim 1,wherein: each R is the same; and R3=R4.
 5. A ligand or catalystaccording to claim 1, wherein R3 and R4 are the same and are—(CH2)_(n)C(O)O-C1-C4-alkyl.
 6. A ligand or catalyst according to claim1, wherein R3 and R4 are selected from the group consisting of —CH2OH,—C(O)O-C1-C6-alkyl, and phenyl.
 7. A ligand or catalyst according toclaim 1, wherein at least one R1 and R2 is a3-C0-C6-alkyl-pyridin-2-yl—C0-C₆-alkyl.
 8. A ligand or catalystaccording to claim 1, wherein Y=1.
 9. A ligand or catalyst according toclaim 1, wherein R3 and R4 are —C(O)O-C1-C6-alkyl.
 10. A ligand orcatalyst according to claim 1, wherein at least one of R1 and R2 isselected from the group consisting of: 3-ethyl-pyridin-2-ylmethyl,pyridin-2-ylmethyl, 3-methyl-pyridin-2-ylmethyl, and6-amide-pyridin-2-ylmethyl.
 11. A ligand or catalyst according to claim10, wherein at least one of R1 and R2 is pyridin-2-ylmethyl.
 12. Aligand or catalyst according to claim 1, wherein both R1 and R2 arepyridin-2-ylmethyl and R is H.
 13. A ligand or catalyst according toclaim 1, wherein X is C═O.
 14. A ligand or catalyst according to claim1, wherein the bleaching composition comprises the free ligand.
 15. Ableaching composition catalyst according to claim 1, wherein thetransition metal catalyst is of the general formula (A1):[M_(a)L_(k)X_(n)]Y_(m)  (A1) in which: M represents a metal selectedfrom Mn(II)-(III)-(IV)-(V), Cu(I)-(II)-(III), Fe(II)-(III)-(IV)-(V),Co(I)-(II)-(III), Ti(II)-(III)-(IV), V(II)-(III)-(IV)-(V),Mo(II)-(III)-(IV)-(V)-(VI) and W(IV)-(V)-(VI); X represents acoordinating species selected from any mono, bi or tri charged anionsand any neutral molecules able to coordinate the metal in a mono, bi ortridentate manner; Y represents any non-coordinated counter ion; arepresents an integer from 1 to 10; k represents an integer from 1 to10; n represents an integer from 1 to 10; m represents zero or aninteger from 1 to 20; and L represents a ligand as defined in claim 1,or its protonated or deprotonated analogue.
 16. A catalyst according toclaim 15, wherein M represents a metal selected fromFe(II)-(III)-(IV)-(V).
 17. A catalyst according to claim 16, wherein Mrepresents a metal selected from Fe(II) and Fe(III).
 18. (canceled) 19.A ligand of formula (I) according to claim 18 or a transition metalcatalyst thereof, wherein at least one of R1 or R2 is pyridin-2-ylmethyland the other is selected from —CH3, —C2H5, —C3H7, and —C4H9.
 20. Aperchlorate salt of dimethyl2,4-di-(2-pyridyl)-3,7-di(pyridin-2-ylmethyl)-3,7-diaza-bicyclo[3.3.1]nonan-9-one-1,5-dicarboxylate(N2Py4).